The present invention relates to tooth prostheses generally and more particularly to crowns.
The following U.S. Patents and publications are believed to represent the current state of the art: U.S. Pat. Nos. 4,129,946; 5,552,390; 5,487,663; 5,624,261; 5,709,548 and 6,106,295.
The present invention seeks to provide a mass-produced, tooth colored pre-fabricated crown, particularly useful in pediatric dentistry for treatment of primary teeth and permanent molars having extensive carious lesions.
There is thus provided in accordance with a preferred embodiment of the present invention an injection molded dental crown formed of an acetal homopolymer, which includes Polioxymethylene (POM) Thermoplastic Homopolymer.
In accordance with a preferred embodiment of the present invention, the injection molded dental crown is formed with depending side surfaces at least one of which defines an undercut.
Preferably, the depending side surfaces are flexible.
There is also provided in accordance with a preferred embodiment of the present invention a method for mass producing dental crowns comprising: providing a multi-element mold, employing the multi-element mold to injection mold the crown including depending side surfaces, at least one of which defines an undercut.
In accordance with a preferred embodiment of the present invention, the multi-element mode includes an ejector which is operative to eject the molded crown following opening of the multi-element mold.